document.write( "Question 1185485: Please help me solve this:A helicopter is travelling upward at a steady velocity of 5 metres per second,when a parcel falls out of the door. 4.2 seconds later the percel hits the ground.
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Algebra.Com's Answer #816419 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "Please help me solve this:
\n" ); document.write( "A helicopter is travelling upward at a steady velocity of 5 metres per second,
\n" ); document.write( "when a parcel falls out of the door. 4.2 seconds later the percel hits the ground.
\n" ); document.write( "a)how high was the helicopter when the parcel fell out?
\n" ); document.write( "b)how high was the helicopter when the parcel hit the ground?
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\n" ); document.write( "\n" ); document.write( "            This problem has a huge underwater stone, which a beginner student can miss.\r
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\n" ); document.write( "\n" ); document.write( "            It is in formulation initial conditions, what influence the governing equation.\r
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\n" ); document.write( "\n" ); document.write( "            The reader should take into account the fact that the initial velocity of the parcel is 5 m/s \r
\n" ); document.write( "\n" ); document.write( "            vertically up, when it detaches from the helicopter.\r
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document.write( "Taking into account, that the initial velocity of the parcel is 5 m/s directed vertically upward, \r\n" );
document.write( "the equation of the height as a function of time is \r\n" );
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document.write( "    h(t) = -5t^2 + 5t + ,\r\n" );
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document.write( "where    is the height of the helicopter, when the parcel detaches it (the unknown value under the first question).\r\n" );
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document.write( "We are given that the parcel got the ground 4.2 seconds after that.  It gives us the equation to find  \r\n" );
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document.write( "    -5*4.2^2 + 5*4.2 +  = 0.\r\n" );
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document.write( "From this equation,   = 5*4.2^2 - 5*4.2 = 67.2 meters.\r\n" );
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document.write( "So, question (a) is just answered.\r\n" );
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document.write( "Question (b) is much simpler.\r\n" );
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document.write( "We simply should add the product  4.2*5 = 21 meter (the rise of the helicopter in 4.2 seconds) to  \r\n" );
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document.write( "    67.2 + 21 = 88.2  meters\r\n" );
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document.write( "to get the answer to question (b).\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "To see many other solved similar and different problems and to learn the subject deeper, wider and better, see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Introductory lesson on a projectile thrown-shot-launched vertically up \r
\n" ); document.write( "\n" ); document.write( "    - Problem on a projectile moving vertically up and down\r
\n" ); document.write( "\n" ); document.write( "    - Problem on an arrow shot vertically upward\r
\n" ); document.write( "\n" ); document.write( "    - Problem on a ball thrown vertically up from the top of a tower \r
\n" ); document.write( "\n" ); document.write( "    - Problem on a toy rocket launched vertically up from a tall platform\r
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\n" ); document.write( "\n" ); document.write( "Consider these lessons as your textbook, handbook, tutorials and (free of charge) home teacher.
\n" ); document.write( "Read them attentively and learn how to solve this type of problems once and for all.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook under the topic \"Projectiles launched/thrown and moving vertically up and dawn\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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